JP3506535B2 - Peelable composite sheet, method for producing the same, and article using the composite sheet - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a peelable composite sheet, a method for producing the same, and an article using the composite sheet.

[0002] Various techniques have conventionally been proposed for releasably covering the surface of a display portion to be concealed, such as a card substrate, by using a composite sheet containing mutually releasable surfaces, such as a composite display label and a display concealment card. Has already been put into practical use.

In this type of technology, various proposals have been made for the peelable bond between the paper and the film, which are the constituent layers of the composite sheet, but the reliability and material of the peel bond for specific individual applications, There is room for improvement in terms of manufacturing costs and the like.

For example, in Japanese Examined Patent Publication No. 55-15035, a polyethylene film that has been cooled and solidified by thermally extruding a thermoplastic resin such as polyethylene onto paper at a temperature lower than a normal lamination temperature, for example, around 290 ° C. is used. There is disclosed a technique for releasably coupling to. In this process, the phenomenon in which the lamination becomes incomplete and the polyethylene film easily peels off as the heat extrusion temperature decreases in the so-called polyethylene lamination process is positively used.For example, polyethylene resin is melt-bonded using paper as a support. In this way, the paper is later peeled off from the polyethylene film.

However, the degree of peel strength, which is important in forming such a peel bond, greatly depends on the temperature and the combination of materials, and while a reliable bond is always formed, this bond surface may be formed if necessary. In practice, it is extremely difficult to obtain a desired peel strength that allows smooth peeling to be always constant only by controlling the melting temperature of the polyethylene resin.

That is, when forming a melt bond between a paper and a resin, if the melting temperature of the polyethylene resin is lowered to a certain extent or more, the thermal activity contributing to the bond is sharply reduced,
It becomes difficult to properly control the peel strength by controlling the temperature. Therefore, 100 g / 2.5 cm is generally desirable for use in articles utilizing composite sheets having a peelable surface.
It is almost impossible to obtain a constant delicate adhesive strength that is easy to peel off. When the temperature is lowered with an emphasis on peelability, peeling easily occurs at a temperature of 290 ° C or less with a slight temperature change. It may happen. On the other hand, if the temperature is raised to a certain degree in order to increase the binding force, the adhesiveness between the paper and the resin will not penetrate by the chemical thermal activation but rather the penetration of the molten polyethylene into the paper fibers or the fineness of the paper surface. The physical binding force due to the entry into the irregularities becomes dominant. In this case, if polyethylene is peeled from the paper while forcibly destroying these physical bonds, part of the paper fibers or paper dust, fluff, etc. are taken in by the polyethylene film side, and transparency is significantly impaired, depending on the paper quality. May cause delamination on the paper side. In the case of peeling off an ultrathin polyethylene film, on the contrary, the film may be damaged on the side.

Therefore, in order to obtain a sufficient bonding force when releasably bonding an ultrathin polyethylene film to paper, unlike the above-mentioned prior art, the melting temperature of polyethylene should be sufficiently heat-activated. It is essential to set the melting temperature at the time of bonding polyethylene to paper so as to cause the above phenomenon as close as possible to the normal lamination temperature. Then, it is necessary to control the peel strength due to the physical bonding force, which naturally increases by increasing the melting temperature of polyethylene in this way, by a separate means.

As described above, as the melting temperature of polyethylene rises, the physical binding force of the polyethylene resin permeates the paper side, etc., but this permeation of polyethylene into the space between the paper fibers is, for example, the tenacity or the paper strength. It depends on the density, and the smoothness of the paper determines whether or not the paper enters the uneven surface. Therefore, by setting the melting temperature of polyethylene close to the lamination temperature and selecting a fine paper having a fineness and a sufficiently high tenacity and smoothness, the binding force by chemical heat activation can be fully utilized to obtain the desired It is expected that smooth peeling can be achieved by obtaining the peeling strength and suppressing the sticking due to the physical binding force as much as possible by the properties of the paper side.

[0009]

The present invention has been accomplished by research and experimentation based on such predictions, and the problems of the prior arts are that the pulp is used as a raw material for a high degree of beating process.
Glassine paper having a calendered smooth surface and fine paper quality, and about 290 to 3 with respect to the glassine paper
A peelable composite consisting of a polyethylene layer which is extruded by heat at a melting temperature of 10 ° C. and is peelably combined by cooling and solidification, and an adhesive layer formed on the outer surface of at least one of glassine paper and polyethylene resin layer. Achieved by the seat.

The peelable composite sheet of the present invention comprises pulp
As a raw material , polyethylene resin was uniformly heat extruded at a temperature of about 290 ° C to 310 ° C on one surface of glassine paper having a highly calcined and supercalendered smooth surface and fine paper quality. The polyethylene resin layer and the glassine paper in a peelable manner, and an adhesive layer is formed on the outer surface of at least one of the polyethylene resin layer and the glassine paper. And a releasable composite sheet comprising the above.

[0011]

In the present invention, a polyethylene resin is uniformly heat extruded at a melting temperature of about 290 to 310 [deg.] C. to adhere to the back surface of the fine glassine paper of paper quality, and then this is cooled and solidified to obtain a glassine. A thin polyethylene resin layer is formed on the back side of the paper . Here, since the polyethylene resin is supplied in the molten state within the above-mentioned temperature range close to the normal lamination temperature, it is sufficiently heat-activated to obtain the glass.
It is evenly adhered to the back side of the paper and is evenly bonded by cooling and solidification. Since this glassine paper inゝhas a large bulk density and smoothness as described above, molten polyethylene resin penetrates the paper plugs維内portion when heat extrusion or fine irregularities on both anchoring in the resin penetrates the surface condition The peel strength is, for example, about 100 g / 2.5 cm.

The glassine paper is generally highly viscous.
Super calendering using unraveled chemical pulp as raw material
So that it has a smooth surface and fine paper quality
Finished products such as medicines, tobacco, foods, etc.
Used in transparent protective packaging against.

The peelable composite sheet of the present invention temporarily hides the surface of various substrates by utilizing the peelable bond formed between the constituent glassine paper and the polyethylene resin layer. Applied to coated or coated articles.

For example, according to the present invention, a card substrate having a display portion to be temporarily hidden, glassine paper and the surface of the glassine paper are heat extruded at a melting temperature of 290 to 310 ° C. and can be peeled off by cooling and solidification. And a composite sheet made of a polyethylene resin combined with the glass sheet , the glassine paper is attached to the display portion of the card substrate through a pressure-sensitive adhesive layer formed on the back surface thereof, and the polyethylene resin of the coating layer is provided. A concealable card having a concealing treatment on the surface of the layer is obtained.

In this concealable card, when the glassine paper side of the composite sheet is adhered to the display portion to be concealed of the card through the pressure sensitive adhesive layer, the concealing treatment is applied to the polyethylene resin layer side. The display portion of the card base material is hidden from the outside. On the other hand, when this composite sheet is peeled between the paper-polyethylene constituent layers, the concealable polyethylene resin layer is peeled off from the glassine paper side, and the transparent glassine paper is left on the display portion of the card substrate to display the indication. It can be read through fluoroscopy.

[0016] The polyethylene resin layer in this case that group
In order to facilitate the peeling from the larch paper , a cutting line may be provided in the portion corresponding to the card display area, and the polyethylene resin layer should be formed to an extremely thin thickness of about 10 μm. Therefore, it can be easily peeled off by simply using a toe.

The peelable composite sheet can be used as a so-called composite display label by further adhering a normal display label paper to the surface of the polyethylene film side via a pressure sensitive adhesive. In this case, when the display label paper on the front surface side is peeled off, the polyethylene resin layer on the lower surface is peeled off to the display label paper side by the pressure-sensitive adhesive having higher adhesive strength, and the display portion of the base material is processed in the same manner as described above. The transparent glassine paper is left behind and the display portion of the adherend (card base material) that is hidden is seen through, and as a result, a label capable of composite display is obtained.

[0018] In a further composite sheet of the present invention Gras
By forming a pressure-sensitive adhesive layer on the outer surface of a polyethylene resin film that is releasably bonded to thin paper , and combining this with an appropriate release paper and winding it into a roll, for decoration or It can also be used as a means for providing transparent film lamination to the surface of articles requiring a protective laminate.

In this case, the release paper is removed from the roll, the composite sheet is adhered to the surface of the article to be laminated by continuously unwinding it with a pressure sensitive adhesive on the polyethylene resin film side, and then the glassine paper. The thin polyethylene resin layer is smoothly adhered and remains on the surface of the article by peeling off the side of, and a transparent film lamination which is the same as that by the lamination method using a conventional laminator or the like is formed.

When peeling the roll end of the glassine paper from the polyethylene resin layer with the fingertips at the time of this peeling, the two layers are bonded by the weak lead adhesion of about 100 g / 2.5 cm as described above. Both layers are easily separated, and only a transparent thin polyethylene resin layer is left in close contact with the surface of the article. By bonding strength between the glassine paper and a polyethylene resin in thisゝis low as described above, always by the peeling action exerted between the two layers Gurashi
The paper side is peeled off, and the polyethylene resin layer does not peel off from the surface of the article against the adhesive strength of the adhesive layer.

In the process of manufacturing the peelable composite sheet, the glassine paper and the polyethylene resin film are adhered to each other by passing between the cooling pressure bonding rollers.
In this case, a desired matting or embossing pattern can be given to the lamination film by providing a fine uneven pattern of an appropriate shape on the roller surface.

[0022]

The present invention will be described in detail below with reference to specific embodiments shown in the drawings. 1 is a sectional view of a concealable card obtained by applying the composite sheet of the present invention, FIG. 2 is a sectional view of a composite display label obtained by applying the composite sheet, and FIG. 3 is a glassine paper -polyethylene resin. It is sectional drawing of the film lamination formation material obtained using a composite sheet, and FIG. 4 is explanatory drawing at the time of giving a film lamination to the article surface by the said material.

(Production of Composite Sheet) A glassine paper (1) having a tightness (JIS P8118) of about 1,000 g / cm ³ is used, and a silicone release paper (not shown) as a process paper is opposed to this. The polyethylene resin extruded from the die of the thermal extruder between the two sheets in this state was extruded at a temperature of about 315 ° C. in an amount such that the film thickness after cooling and solidification was about 11 μm.

Next, the melted polyethylene resin layer (2)
The glassine paper (1) and the release paper sandwiched between were continuously fed while being pressed by a cooling roller, whereby the molten polyethylene resin layer (2) was bonded to the glassine paper (1). After completion of cooling and solidification, the silicon release paper on the back surface was removed, and a composite sheet in which the polyethylene resin layer (2) was bonded to the glassine paper (1) at a peel strength of about 100 g / 2.5 cm as shown in FIG. Obtained. The composite sheet is generally transparent due to the high transparency of the glassine paper (1) and the polyethylene resin layer (2), and the polyethylene resin layer side is subjected to concealment printing or the like for the concealment purpose described later. The grayed
A transparent acrylic pressure-sensitive adhesive (3) was applied to the lower surface of the lathin paper (1) over the entire surface to a thickness of about 20 μm.

(Hidden card) There is a description that you want to hide temporarily in the display print column (4)
On the surface of the postcard (5) as a card substrate for
Of theGlassine paper(1) as the pressure sensitive adhesive layer (3)
Therefore, when bonded, the concealment mark of the polyethylene resin layer (2)
The display of the display print column (4) is surely hidden by the printing (6).
To be hidden. The recipient uses a knife or knife over the surface of the composite sheet.
Remove the thin polyethylene resin layer (2) when peeled off with the tip of the toe
Easy to peel off at the possible adhesive surface (S)Glassine paper
(1) is left on the display print field (4).Glassine paper
(1) Substantially transparent and solvent-type transparent feeling
Since the pressure-sensitive adhesive (3) has penetrated into part of it, it is a marking
This is the printing column (4)Glassine paperClear perspective through (1)
can do.

(Composite display label) In the application example shown in FIG. 2, a predetermined display label paper (8) is further formed on the upper surface of the polyethylene resin layer (2) of the composite sheet shown in FIG. 1 via a pressure sensitive adhesive (7). ) Is adhered, and an appropriate perforation line (9) that gives a trigger for peeling near the outer edge of the label sheet (8).
It has the same configuration as the concealed card except that the above-mentioned concealed card is formed.

In this composite display label, the quality of the display label paper (8) and the display print column (10) itself as the first display portion applied to the display label paper (8) make the second label substrate (11) second. It is given a sufficient hiding properties to the display unit (12), when you peel off the label paper (8), adhesion resin over the pressure sensitive adhesive for the polyethylene resin layer (2) (7) glassine Since it is larger than the adhesive force between the papers, only the glassine paper (1) is left on the first display portion (12) of the label base material (11) at the time of peeling so that it can be seen through. Therefore, in this example, a so-called composite display label can be obtained in which two types of display, that is, the original display label paper 8 and the display that appears on the side of the base material 11 after the peeling are provided.

(Film Lamination Forming Sheet) In this example, the peelable composite sheet obtained as described above is applied to the use for forming a so-called film lamination for protection or decoration on the surface of an article.
As shown in FIG. 3, a transparent pressure-sensitive adhesive (13) is formed on the surface of the polyethylene resin layer (2) of the composite sheet, and a silicone release paper (14) is combined with the transparent pressure-sensitive adhesive (13) and rolled up, for example, in a roll shape. deep. In this case, the surface of the glassine paper (1) itself may be siliconized to omit the use of release paper.

In use, while unrolling the roll of the composite sheet, the pressure sensitive adhesive (13) on the polyethylene resin layer (2) side is exposed except for the silicone release paper (14), as shown in FIG. The polyethylene resin layer (2) side is sequentially and continuously adhered to the surface (15) of a predetermined article such as a plywood board requiring lamination by the pressure sensitive adhesive layer (13). Then the cause peeling to the side of glassine paper (1) from the end portion, the smooth peeling peelable surface (S) between the polyethylene resin <br/> over glassine paper occurs as the surface of the article (15 The transparent polyethylene resin layer (2) is left in (), and a lamination coating exactly the same as the one using a conventional laminator can be obtained very easily.

In this case, the adhesive force of the polyethylene resin layer (2) to the surface (15) of the article by the pressure sensitive adhesive (13) and the adhesive force between the glassine paper (1) and the polyethylene resin layer (2). As described above, there is a clear difference, so that the polyethylene resin adhered to the article by the polyethylene resin layer (2) between the surface (15) of the article and the glassine paper (1). There is no risk of wrinkles or breakage in the layer (2), and film lamination can be performed smoothly by an extremely simple operation without using a special extrusion device.

[0031]

As described above, in the present invention, the composite sheet produced as described above is required as a constituent layer for glassine paper having sufficient tenacity and smoothness, and for bonding to it. Since it has a polyethylene resin layer fused at a temperature sufficiently high to generate various thermal activities, it is possible to stably obtain a preferable bonding force for peelable bonding between both constituent layers. That is, this composite sheet can be basically manufactured by a very simple procedure in which molten polyethylene resin is formed on glassine paper by a heat extrusion method and then cooled and solidified, and the layer structure is simple. Thus, the material cost and hence the manufacturing cost of the article to which it is applied can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a concealable card obtained by applying a glassine paper -polyethylene resin composite sheet manufactured by the method of the present invention.

FIG. 2 is a cross-sectional view of a composite display label obtained by applying the composite sheet.

FIG. 3 is a cross-sectional view of a material for forming a transparent film lamination on the surface of an article obtained by using the glassine paper -polyethylene resin composite sheet.

FIG. 4 is an explanatory diagram showing a state in which film lamination is formed on the surface of an article using the material shown in FIG.

[Explanation of symbols]

1 Glassine Paper 2 Polyethylene Resin Layer 3 Pressure Sensitive Adhesive Layer 4 Display Printing Column 5 Postcard Base Material 6 Concealment Printing 7 Pressure Sensitive Adhesive Layer 8 Display Label Paper 9 Cut Lines 10 Second Display Section 11 Label Base Material (Adhered Body) ) 12 1st display part 13 Pressure-sensitive adhesive 14 Release paper 15 Article

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI G09F 3/10 G09F 3/10 A (58) Fields investigated (Int.Cl. ⁷ , DB name) G09F 3/03 B32B 7 / 06 B32B 7/12 B32B 27/10 B42D 15/02 501 G09F 3/10

Claims (2)

(57) [Claims] 1. A highly beating soot made from pulp.
A glassine paper having a smooth surface and a fine paper quality that is calendered, and about 290 to the glassine paper .
A peelable composite comprising a polyethylene layer which is extruded by heat at a melting temperature of 310 ° C. and is peelably combined by cooling and solidification, and an adhesive layer formed on the outer surface of at least one of glassine paper and a polyethylene resin layer. Sheet. 2. A highly beating soot made from pulp.
A polyethylene resin is heat extruded at a temperature of about 290 ° C. to 310 ° C. and uniformly adhered to one surface of a glassine paper having a smooth surface and a fine paper quality that have been calendered, and then cooled and solidified to form the polyethylene resin. becomes the a layer glassine paper and releasably coupled to, and method of manufacturing the peelable composite sheet which comprises forming an adhesive layer on at least one of the outer surface of the polyethylene resin layer and glassine paper.